The weapon was a Nerf Stampede which was hacked so it could be fired electronically. The safety switch was bypassed and a relay provided the firing signal. The electronics stack consists of an Intel Galileo, a motor shield and a relay shield. The turret assembly was built using off the shelf structural parts from Actobotics. Stepper motors provide motion to the turret. The fun begins with how the software is implemented. An iBeacon network detects where people sit at in the office. So when you type in the name of your target in a messaging app, it knows where they’re sitting, aims at them, and pops a nerf dart at them.

The lessons learned are what makes such projects worth their while. For example, USB is a standard. And the standard says that USB cables be not more than 1.8 m long. [Seb] was reminded of this when his electronics worked on his workbench, but refused to work when placed in-situ and connected via a 3m long cable – the serial link just wouldn’t work.

Mounting the gun such that it was nicely balanced was another challenge. Eventually, he had to use a couple of AA cells taped to the front of the gun to get it right. This could be useful though, since he plans to replace the dead weights with a sighting camera. One last hack was to zip tie heat sinks to the motor drivers, and he had a good reason to do that. Read more about it in his blog. And check out the video as someone takes aim and shoots a target via SLACK, the team messaging application.

If you work with a bunch of sticky-fingered co-workers, your desk is going to need protecting -- especially when you're away at lunch. This 3D-printed sentry gun from Swiss engineering student Kevin Thomas is motion-activated and fires a 6-round clip of rubber bands at anybody foolhardy enough to come within range. It's controlled with an Arduino chip running Thomas' version of the open-source Project Sentry Gun software. And if you don't want to let the sentry gun have all the fun, you can also switch it from autonomous mode and manually aim it using a joystick. With all the eyes you'll put out and SBC violations you'll incur with this menacing mechanization, you and the HR department are going to become such good friends.

[Jon] and his brother converted an RC car into a robot that can fire airsoft pellets into the air. The little motorized vehicle was disassembled and a handheld was attached to the top. A pulling mechanism was put in place and a safety procedure was added to make sure no accidents occurred.

An Arduino was used to get the servo working, and a chassis stand was created to hold the handle. The setup was then tested at this point, and a Raspberry Pi server was configured to install a motion sensing camera that would act as the eyes for the robot. Once everything was in place, the wheels hit the ground and the vehicle was able to move around, positioning itself to aim the servos at a designated target. Footage was transmitted via the web showing what the robot was looking at.